Vae victis!

I downloaded the HQ sound patch (https://www.moddb.com/mods/hq-audio-patch/downloads/hq-sound-patch-v3) but I don't know how to install it. I'm using the current base version of the game from GOG. Do I just drag, drop, and replace the files, or is there something more to it? The instructions from the download site are confusing to me.

I'm fine with everything else in the game, so improving the sound is the only mod I want.

Edit: I forgot to tag this as a question.

Step 1: Go into the game's folder "C:/GOG Games/Blood Omen/KAIN/" with PILL.BIG and rename it to something else.
Step 2: Go into the "Main/xdeltaUI" folder and launch xdeltaUI.exe.
- If your game is located in one of the "Program Files" folders, run xdeltaUI.exe as an administrator.
Step 3: Select "bohqsound.xdelta" as the patch file.
Step 4: Select the renamed PILL.BIG file from your installation as the source file.
Step 5: For the output file, name it "PILL.BIG".

Checksum of the patched PILL.BIG should be: eca343e0fadabdbd191f4b8622d1d1d4

BTW, Verok's GL wrapper & patch "KainGL_1.75_MULTI11_FullPackage.7z" is compatible with GOG version, and you only need to unpack it to the main folder of the game. It's useful in fixing camera.